Internal-combustion engine



G. B. GERAU.

INTERNAL'COMBUSTION ENGINE.

APPLICATION FILED JAN. 29, 1920.

1 ,41 7,727. Patented May 30, 1922.

2 SHEETS-SHEET l- 9 5 Ger-tau.

@Hrozueg G. VB.-GERAU. INTERNAL COMBUSTION ENGINE.

'APPLICATION FILED JAN. 29, 1920.

INVENTOR Georyefl Gerau. BY

ATTORNEYS WITNESSES UNITED STATES GEORGE BALDWIN GERAU, or MIAMI, FLORIDA.

INTERNAL-COMBUSTION ENGINE.

Specification of Letters Patent.

Patented May 30, 1922.

Application filed January 29, 1920. Serial No. 354,868.

To all whom it may concern Be it known that I, GEORGE BALDWIN GERAU, a citizen of the United States, and a resident of Miami, in the county of Dade and State of Florida, have invented certain new and useful Improvements in Internal-Combustion Engines, of which the following is a specification.

My invention relates to improvements in internal combustion engines, it being more particularly an improvement on the engine disclosed in my co-pending application filed March 8, 1918, Serial No. 221,246, and it consists in the constructions, combinations and arrangements herein described and claimed.

One of the foremost objects of the invention is to provide a multi-cylinde'r two-cycle engine, so operatively arranged that the influx of anew char e is not depended on to scavenge the cylimisr of a previously burnt charge.

Another object of the invention is to pro vide an engine of the class described, which employs a trunk piston having a main head operating in the explosion chamber, an auxihary head operating in a combined air and gas pumping chamber, the air pumplng action occurring near the end of a working stroke to scavenge the explosion chamber of the burnt gas before a new charge is let in;

and a pair of semi-circular or shuttle valves cooperating with the piston, with actuating means controlled by the crosshead of the connecting rod.

A further object of the invention is to provide an engine wherein the cylinders work in pairs, the, piston of one cylinder forcing a new charge of gas into the explosion chamber of the other cylinder when the piston of that chamber is near the outer extremity of itsstroke, and vice verse. 1

Other objects and advantages will appea in the following specification, reference beinlg had to the accompanying drawings, in

w ich:

Figure 1 is a vertical section of the upper part of one cylinder of the engine, showing the piston on its lnward or compression stroke,

Figure 2 is a horizontal section on the hue 2-2 of Figure 1, showing how the fresh gas is forced by the piston of one cylinder into the explosion chamber of the other cylinder, Figure 3 is a horizontal section on the line 3-3 of Figure 1, showing the arrangement of the gas inlet ports and the semicircular or shuttle valves,

igure 4 is a diagram illustrating the pos1t 1on of the parts atthe occurrence of the primary exhaust wherein the major body of the burnt gas is expelled byrvirtue of its own impetus,

Figure 5 is a similar view illustrating the positlon of the parts when the scavenging influx of compressed air drives out the residue of the burnt charge, and

Figure 6 is a similar view illustrating the position of the parts when a fresh charge is about to be forced into the left cylinder.

The general construction of the engine, considering one unit only at this time, consists of a cylinder 1, suitably water jacketed at 2 and provided with a cap 3 which has a centrally pendent extension 4 terminatin in a stationary head 5. The extension 4 is 01- low to permit the insertion of the spark plug 6 in the head 5, and to admit air to the radial passages 7 which lead into the air chamber 8.

The main head 9 of the trunk piston 10 works in conjunction with the under side of the stationary head 5, while the auxiliary head 11 of the same piston works in conjunction with the upper side of the head 5, or

at least with so much thereof as is exposed around the extension 4 in the air chamber 8-. The reciprocations of the auxiliary head 11 cause air to be drawn in and forced out of the passages 7 and thereby aid in keeping the parts cool.

That portion of air remaining in the chamber 8 after the auxiliary head 11 covers the radial passages 7 on the outward stroke of the piston 10, becomes highly compressed and is injected into the explosion chamber 12 when the air ports 13, 14 become disposed at opposite sides of the head 5 and joined in communication by the duct 15 in the right shuttle valve 16. This action occurs at the second exhaust wherein the residue of the burnt charge is expelled b the injection of compressed air, prior to t e admission of a. fresh charge.

The crosshead 17 of the pitman 18 has ears to which the links 19 and 20 of the valves 16 exhaust port 22 registrable with a similar port 23 in the shuttle valve 16 at the right, and a secondary exhaust port 24 similarly registrable with a corresponding port 25 in the same valve. On the other side, the piston has a gas intake port 26 registrable with a corresponding port 27 in the shuttle valve 21.

Two reservoirs 28, 29 hold fresh gas pumped therein by the auxiliary pistons 11, 11 of the companion cylinders illustrated in Figure 2. One piston supplies the explosion chamber 12 of the other cylinder, and

vice versa. For example, the auxiliary head 11 forces fresh gas taken in at the intake passage 30, over in the direction of the arrow a, through the valved'hole 31 in the top web connecting the two cylinders and into the explosion chamber 12 through the cylinder intake port 32, when the ports 26, 27 are in proper position to'permit this action. Similarly, the auxiliary head 11 forces fresh gas taken in at the passage 33, over in the direction of the arrow 6, through the valved hole 34 in the top web and into the explosion chamber of the cylinder at the top in Figure 2 through the cylinder intake port 35, when the mechanism of that cylinder is in proper position to permit this action.

The primary exhaust occurs when the primary exhaust ports 22, 23 at the right, come into registration with the upper port 36 of the exhaust manifold 37 This primary exhausting action occurs after the crank has travelled approximately 105 in Figure 4, and the primary exhausting action continues through approximately 30 additional of rotation until the posltion in Figure 5 is reached,

It is during this primary exhausting of the explosion chamber 12, that the greater volume of the burnt gas is expelled by virtue of its own force or impetus. The reader will understand at once that when the 105 position in Figure 4 is reached, the pitman 18 will be in such a position that the shuttle valve 16 will have been slid upwardly so as to fully register the primary exhaust ports 22, 23.

Then in moving from the 105 to the 135 position, the registered ports will move over the upper exhaust port 36 and thereby permit the gas expulsion just mentioned.

The secondary exhaust commences at the 135 position in Figure 5 and continues for approximately 15 additional of rotation of the crank, until the 150. position in Figure 6 is reached. The secondary exhaust is ac complished by the injection into the explosion chamber 12 of a charge of compressed air coming through the ports 13, 14' and duct 15 then in registration.

As clearly shown in Figure 5, these various ports and duct provide a by-path around the stationary head 5, permitting the air entrapped in the air chamber 8 between the auxiliary head 11 and the fixed head 5, to

11 of the piston at the right, will force a charge of gas over into the explosion chamber 12 at the left as the two cranks move through the remaining 30 to reach the extremities of the respective outward and inward strokes.

The greatest influx of fresh gas into the explosion chamber 12 occurs through the 30 movement just referred to, because it is through thismovement that the piston '11 on the right acts as a pump, forcing the gas over through the hole 31 and reservoir 28, as indicated by the arrow a in Figure 2. The intake ports 26, 27 are in proper registration at that time with the cylinder intake port 32, so as to permit the function described. When the crank pin of the trunk piston 10 nears the outermost extremity of its circle of movement, the top of the auxiliary head 11 uncovers the intake passage 33 so that a fresh charge of gas rushes into 7 the chamber 8 above the auxiliary head, in readiness to be forced into the reservoir 29 on the return or inward movement of the piston.

It is thus seen that the chamber 8 is a gas chamber above the auxiliary piston head 11, and an air chamber beneath that head, as already fully pointed out. After the functions of taking in a fresh charge in the explosion chamber 12 and in the gas cham-' ber above the auxiliary'head 11 have been accomplished, the gas in the chamber 12 is compressed by the inward movement of the head 9, and is ignited at the proper time, whereupon the foregoing cycle of,

operation is completed.

While the construction and arrangement of the improved internal combustion engine as herein described and claimed, is that of a generaHy preferred form, obviously modifications and changes can be made without.

departing from the spirit of the invention or the scope of the claims.

I cla1m:

1. An internal combustion engine, comprising a pair of cylinders, with'inte ral connecting and separating webs arrange to define a gas reservoir for each cylinder and including a cylinder intake port leading to each explosion chamber; and a piston in each c linder one forcing freshgas on the inwar stroke, into the reservoir, cylinder port and explosion chamber of the other cylinder when that piston nears the extremity of its outward stroke, and vice Versa.

2. An internal combustion engine, comprising a cylinder with explosion and air chambers, and a piston having a head inwith one of the exhaust ports near the end of the outward stroke, and subsequently effect a secondary registration with the other portlater in said stroke.

4. An internal combustion engine, comprising a cylinder with primary and secondary exhaust ports, and a pendent stationary head defining air and explosion chambers respectively above and below said head; a trunk piston with auxiliary and main heads in the respective chambers and separated primary and secondary exhaust ports; and a piston-carried valve with one port slidable into registration with all primary exhaust ports for the initial self-expansion of burnt gas on a part of the outward piston stroke, and a second port subsequently registrable with all secondary exhaust ports for the final forcible expulsion of the residuum by compressed air conducted from the air chamber.

5. An internal combustion engine, comprising a pendent stationary head defining a portion of an explosion and air chamber above and below the head, a trunk piston occupied by said head, having a main head completing the explosion chamber, and an auxiliary head completing the air chamber, with separated air ports disposed at opposite sides of the stationary head when the piston reaches a predetermined position in the outward stroke; and a piston-carried valve, with a duct then registering with both ports to enable the injection into the explosion chamber of air compressed in the air chamber to perform a scavenging function.

6. An internal combustion engine, including a ported pitman-reciprocated piston, and a pair of correspondingly ported semi-circular valves embracing the piston, with link connections to opposite sides of-the crosshead of the pitman, by which they are slid in opposite directions as the piston reciprocates.

7. In an internal combustion engine, a

cylinder with a pendent extension, withair passages, having a terminal head; a piston in the cylinder, having a head defining an air chamber with the terminal head, forcing air through said passages during the first part of its inward stroke, but compressing residual air during the last part after said passages are closed by the piston head; and associated valve mechanism for controlling the compressed air.

8. In an internal combustion engine, a cylinder with a pendent extension provided with air passages and an end head, a piston in the cylinder, with a head defining an air chamber above the end head, and having ports adjacent its head; and a valve carried by the piston, with a bridge port to embrace the piston port when the piston head compresses air 1n the 'air chamber, and trarasfer the compressed air beneath the end hea I GEORGE BALDWIN GERAU. 

